The influence of genetic factors on physical functioning and exercise in second half of life

During the past decades, a number of studies of families and twins in particular have assessed the relative contribution of genetic and environmental factors to traits reflecting various aspects of physical functioning: maximal O2 uptake, muscular endurance, muscular strength, muscle cross sectional area, flexibility, and trainability. Although the estimate of the size of the genetic component differs between the various studies, they point towards a moderate to substantial genetic influence on these phenotypes. Most of the studies have used only young and healthy study subjects, although in recent years phenotypes of particular importance to the elderly and the oldest-old (e.g., activities-of-daily living abilities) have also been shown to have substantial genetic component. Furthermore, behavioural studies have also revealed a genetic contribution to the disposition to level of leisure time physical activity. At present, there is still a few association studies on specific genetic variants, and the results have either been inconsistent or failed to show an association with physical functioning. Therefore, the mechanisms through which the genetic influence is expressed, is still an enigma. Here, we summarise the evidence currently available for a genetic influence on physical functioning and disposition to leisure time physical activity with a focus on recent Danish twin data.     

Gadolinium-enhanced magnetic resonance imaging predicts response to methylprednisolone in multiple sclerosis

Oral high-dose methylprednisolone treatment is efficacious in acute optic neuritis (ON) and attacks of multiple sclerosis (MS). The responses to treatment in subgroups of patients participating in two randomized, controlled trials were assessed. Fifty-eight patients with ON and 51 patients with attacks of MS were treated with placebo or oral methylprednisolone (500 mg daily for five days with a 10-day tapering period). A gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) scan was obtained at baseline in 66 patients, and 29 patients underwent repeated MRI studies. Seventy-four patients underwent lumbar puncture before treatment. The odds ratio (OR) of improvement after methylprednisolone treatment (a one point change in the visual function system score of the Kurtzke Expanded Disability Status Scale (EDSS) in ON or in the EDSS score in attacks of MS) was higher in patients with enhancing lesions on baseline MRI (one week: OR 15, P = 0.02; eight weeks: OR 4.6, P = 0.02). Methylprednisolone treatment suppressed Gd-enhancement after one week (P < 0.001) and three weeks (P = 0.001). Cerebrospinal fluid measures of intrathecal inflammation correlated with the area of Gd-enhancement but did not correlate as closely with the treatment response as did the results of Gd-enhanced MRI. These findings suggest that the resolution of intrathecal inflammation as assessed by Gd-enhanced MRI is a major effect of oral high-dose methylprednisolone.     

Use of cultivation-dependent and -independent techniques to assess contamination of central venous catheters: a pilot study

Background  

Catheters are the most common cause of nosocomial infections and are associated with increased risk of mortality, length of hospital stay and cost. Prevention of infections and fast and correct diagnosis is highly important.     

Localized in vivo proton spectroscopy in the brain of patients with multiple sclerosis.

Localized proton spectroscopy was performed in 15 patients with acute or chronic multiple sclerosis (MS). Some of the patients were investigated serially, being given a total of 22 spectroscopic investigations. Resonances corresponding to free lipids were observed in six plaques. This was distinctly seen in two plaques at Days 70 and 85 after the occurrence of the plaques. A lesser content of lipids in plaques was observed as early as Day 10 and as late as nearly 1 year after occurrence. The relative concentration of N-acetyl asparate (NAA) was significantly lower in patients than in controls, and the relative concentration of choline (Cho) was significantly higher in patients than in controls. These differences were most pronounced in older plaques. MR spectroscopic demonstration of lipids in a MS plaque probably reflects disintegration of myelin, and a decreased NAA/Cho ratio may be related either to gliosis or to axonal degeneration, which sometimes occurs in longstanding MS.     

Physiologic changes in pregnancy and their effect on drug disposition.

Changes in maternal physiology occur normally during pregnancy and have the potential to alter the absorption, distribution, and elimination of drugs used therapeutically in pregnant women. These physiologic changes include: plasma volume expansion and increases in extracellular fluid space and total body water; decreased plasma albumin concentration; a compensated respiratory alkalosis; increased cardiac output with regional blood flow changes; increased renal blood flow associated with increased glomerular filtration; changes in hepatic drug metabolizing enzymes; and changes in gastrointestinal function. These changes begin in early gestation but are most pronounced in the third trimester of pregnancy. Further maternal physiologic changes occur intrapartum with some normalizing themselves within 24 hours of delivery, while others are sustained only returning to normal some 12 weeks postpartum. These physiologic changes form the basis for the need for pharmacokinetic studies during pregnancy.     

Indium-111-granulocyte scintigraphy in brain abscess diagnosis: limitations and pitfalls

The scintigrams and records of 28 patients referred for indium-111-granulocyte scintigraphy (111In-GS) because of a suspected brain abscess were studied retrospectively. The final diagnosis was brain abscess in 8 patients, brain tumor in 18 patients, and infarct and hematoma in 1 patient each. Five patients not on corticosteroid treatment showed intense focal 111In accumulation in abscesses, whereas an abscess patient receiving a high steroid dose showed no uptake. Two patients studied twice showed intense uptake in abscesses when not on steroid therapy or on a low dose, whereas no uptake was seen when they received high or medium doses. Weak or moderate 111In uptake was observed in nine tumors. Microscopically assessed degree of tumor granulocyte infiltration, vessel proliferation, and hemorrhage did not correlate with the outcome of 111In GS. Our results suggest that intense focal cerebral 111In uptake favors the abscess diagnosis. Abscesses may go undetected, however, in patients on high- or medium-dose steroid therapy.